I have Freeswitch running in an Alpine VM with a Sangoma gateway downstream. Until recently I was using Freeswitch 16 and it was working fine, but due to an OS upgrade, it seemed reasonable to upgrade to Freeswitch 18 (the version that comes with that Alpine release). However, now upstream calls from the Sangoma fail. Specifically, when FS sends the 200 OK (for the Invite), the Sangoma now does not reply with ACK, and so FS tears down the call after 30 sec. I tried the 'connectile dysfunction' parameter, but this did not seem to have any positive effect. In fact, it was perhaps worse because the Register (from Sangoma to FS) seems to get stuck in a loop, with Sangoma sending the request over and over back to back. I would be interested to hear if this rings a bell with anyone? Are there any crucial differences in base config between 16 and 18 that would change the behaviour? Regards, Martyn